Ellington Residential Mortgage REIT is a real estate investment trust. The Company conducts its business through its subsidiaries, EARN OP GP LLC and Ellington Residential Mortgage LP (the Operating Partnership). It specializes in acquiring, investing in and managing residential mortgage- and real estate-related assets. It constructs and managing a portfolio consisting of residential mortgage-backed securities (RMBS) for which the principal and interest payments are guaranteed by the United States Government agency or the United States Government-sponsored entity (Agency RMBS) and, to a lesser extent, RMBS backed by prime jumbo, Alternative A-paper manufactured housing, and subprime residential mortgage loans (non-Agency RMBS). Its Agency RMBS include residential mortgage pass-through certificates, collateralized mortgage obligations (CMOs) and to-be-announced mortgage pass-through certificates (TBAs). Its non-agency RMBS include investment grade and non-investment grade classes.